So far, we know next to nothing about Season 5. There were vague plans before the layoffs to have "expansion-like" content on the living world, but we have no idea if that will remain, or if the Season 5 will follow the idea of not adding a new map per release, or anything else really.
One kind of popular content that could be classified as "expansion-like" would be new specializatons. I have seen a few people wondering if the recent changes to skill types would be a sign of ArenaNet playing with ideas for new specializations (like the command skills for rangers and the preparation skills for thieves).
Do you think we will get new elite specializations in the next season of the Living World?
"Tomorrow my master chokes on his own whip!" - Lore of Skaen, PoE